Method for depositing a topcoat layer on a face of a substrate and flexible deposition device

Abstract

A method for depositing a topcoat layer on, at least, one face of a substrate, includes the steps of: a) providing a flexible deposition device including a flexible supporting medium having a supporting surface coated with a film of a topcoat material; b) bringing into contact the film of topcoat material of the flexible deposition device with the face of the substrate; c) applying a pressure on the flexible supporting medium so that the flexible deposition device conforms to the geometry of the face of the substrate; and d) peeling off the flexible supporting medium from the substrate, whereby the topcoat material is at least partially separated from the flexible supporting medium and deposited on the contacted face of the substrate to form the top coat layer.

1 . A method for depositing a topcoat layer on, at least, one face of a substrate, comprising the steps of:
 a) providing a flexible deposition device comprising a flexible supporting medium having a supporting surface coated with a film of a topcoat material,   b) bringing into contact said film of topcoat material of the flexible deposition device with said face of the substrate,   c) applying a pressure on the flexible supporting medium so that said flexible deposition device conforms to the geometry of said face of the substrate, and   d) peeling off said flexible supporting medium from said substrate, whereby the topcoat material is at least partially separated from the flexible supporting medium and deposited on the contacted face of the substrate to form said top coat layer.   
     
     
         2 . Method of  claim 1 , wherein said supporting surface of the flexible supporting medium has a lower surface energy than said contacted face of the substrate. 
     
     
         3 . Method according to  claim 2 , wherein the static contact angle of the supporting face of the supporting medium with water is comprised between 40° and 130° and the static contact angle of the substrate with water is comprised between 0° and 60° and is smaller than the one of the supporting medium. 
     
     
         4 . Method according to  claim 1 , wherein the layer of topcoat material on the flexible supporting medium has a thickness comprised in the interval [10 nm, 300 nm]. 
     
     
         5 . Method according to  claim 1 , wherein, at step c), the topcoat material is maintained at a temperature comprised between room temperature and 40° C. 
     
     
         6 . Method according to  claim 1 , wherein, step a) comprises the steps of
 a1) providing a flexible supporting medium and   a2) coating at least one of its surfaces with said film of topcoat material by dipping the supporting medium in a solution containing said topcoat material, by spin-coating or spraying said topcoat material on the surface of the supporting medium, by wiping the topcoat material onto the supporting medium or by evaporating said topcoat material onto the supporting medium in an evaporator.   
     
     
         7 . Method, according to  claim 6 , wherein an additional step a1bis) of treating the surface of the flexible supporting medium with treatments to reduce its surface energy, is applied between step a1) and step a2). 
     
     
         8 . Method according to  claim 1 , wherein, the substrate provides at step c) is one of a bare substrate comprising anti-abrasion or anti-scratch coating as outermost layer, or a substrate comprising an anti-reflective stack with one of the layers of the antireflective stack as the outermost layer on the substrate. 
     
     
         9 . Method according to  claim 1 , wherein, before contacting step b), said face of the substrate is treated, e.g. by plasma or corona treatment, to increase the surface energy of said face of the substrate. 
     
     
         10 . Method according to  claim 1 , further comprising, after step d), a step e) wherein the topcoat material deposited on said face of the substrate is subjected to a fixing treatment and a step f) of removing any excess of unfixed topcoat material, e.g. through wiping. 
     
     
         11 . Method according to  claim 1 , wherein the topcoat layer deposited on said face of the substrate is an antifog layer, an antifouling layer, an antisoiling layer, a hydrophilic layer, a hydrophobic layer, or an omniphobic layer. 
     
     
         12 . Method according to  claim 1 , wherein the thickness of the topcoat layer formed on said face of the substrate is equal to or lower than 100 nm, preferably equal to or lower than 50 nm, more preferably equal to or lower than 10 nm. 
     
     
         13 . A flexible deposition device comprising a flexible supporting medium having a supporting surface coated with a film of topcoat material, said flexible supporting medium being adapted to allow deposition of at least part of the topcoat material to form a topcoat layer on a face of a substrate by using the method according to  claim 1 . 
     
     
         14 . Flexible deposition device according to  claim 13 , wherein the film of topcoat material is sandwiched between, on one side, the flexible supporting medium, and on the other side, a removable tape having lower surface energy than said supporting surface, said removable tape being removed before step a) of said method. 
     
     
         15 . Flexible deposition device according to  claim 13 , wherein said flexible supporting medium is made of an inert material with regard to said topcoat material.